Field of the Invention
The present invention relates to an optical system, an optical apparatus equipped therewith, and a method for manufacturing the optical system.
Related Background Art
A retrofocus lens having a leading lens group with negative refractive power has been known as a wide-angle optical system securing a back focal length sufficient for a single-lens reflex camera and a digital camera in spite of a short focal length. In such a lens type, there has been known a one having a large aperture of an f-number of 1.4 (for example, see Japanese Patent Application Laid-Open No. 11-030743). Regarding such an optical system, request for suppressing ghost images and flare, which deteriorate optical performance, as well as aberrations become increasingly strong. Accordingly, a higher optical performance is required to antireflection coatings applied to a lens surface, so that in order to meet such request, multilayer design technology and multilayer coating technology are continuously progressing (for example, see Japanese Patent Application Laid-Open No. 2000-356704).
However, when a vibration reduction mechanism is applied to a conventional wide-angle optical system, correction of aberration upon vibration reduction is not sufficient. In addition, there is a problem that reflection light producing ghost images and flare is liable to be generated from optical surfaces in such an optical system.